/src/freeradius-server/src/lib/util/cbor.c

Source
/*
 *   This library is free software; you can redistribute it and/or
 *   modify it under the terms of the GNU Lesser General Public
 *   License as published by the Free Software Foundation; either
 *   version 2.1 of the License, or (at your option) any later version.
 *
 *   This library is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 *   Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public
 *   License along with this library; if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */

/** CBPR encoding and decoding
 *
 * @file src/lib/util/cbor.c
 *
 * @copyright 2024 Network RADIUS SAS (legal@networkradius.com)
 */
RCSID("$Id: 8f2fd049283373f80677caa5f759cdca30f0ec4c $")

#include <freeradius-devel/util/cbor.h>

#define CBOR_INTEGER  (0)
#define CBOR_NEGATIVE (1)
#define CBOR_OCTETS (2)
#define CBOR_STRING (3)
#define CBOR_ARRAY  (4)
#define CBOR_MAP  (5)
#define CBOR_TAG  (6)
#define CBOR_FLOAT  (7)

#define CBOR_1_BYTE ((uint8_t) 24)
#define CBOR_2_BYTE ((uint8_t) 25)
#define CBOR_4_BYTE ((uint8_t) 26)
#define CBOR_8_BYTE ((uint8_t) 27)

static const char *cbor_type_to_str[8] = {
  "integer", "negative", "octets", "string",
  "array", "map", "tag", "float"
};

/*
 *  Some of our data types need tags.
 *
 *  We don't have a tag to data type array.  When decoding, we should usually have the enclosing pair
 *  number, which includes our data type.  If the tag type doesn't match the value here, then something is
 *  wrong.
 */
static const uint64_t cbor_type_to_tag[FR_TYPE_MAX + 1] = {
  [FR_TYPE_DATE] = 1,
  [FR_TYPE_ETHERNET] = 48,
  [FR_TYPE_IPV4_ADDR] = 52,
  [FR_TYPE_IPV4_PREFIX] = 52,
  [FR_TYPE_IPV6_ADDR] = 54,
  [FR_TYPE_IPV6_PREFIX] = 54,
  [FR_TYPE_TIME_DELTA] = 1002,
};

static fr_type_t cbor_guess_type(fr_dbuff_t *dbuff, bool pair);

static ssize_t cbor_encode_integer(fr_dbuff_t *dbuff, uint8_t type, uint64_t data)
{
  fr_dbuff_t  work_dbuff = FR_DBUFF(dbuff);
  uint8_t   value[8];

  fr_assert(type < 8);
  type <<= 5;

  if (data < 24) {
    data |= type;

    FR_DBUFF_IN_BYTES_RETURN(&work_dbuff, (uint8_t) (data & 0xff));
    goto done;
  }

  if (data < (((uint64_t) 1) << 8)) {
    value[0] = data;

    FR_DBUFF_IN_BYTES_RETURN(&work_dbuff, (uint8_t) (type | CBOR_1_BYTE));
    FR_DBUFF_IN_RETURN(&work_dbuff, value[0]);
    goto done;
  }

  if (data < (((uint64_t) 1) << 16)) {
    fr_nbo_from_uint16(value, data);

    FR_DBUFF_IN_BYTES_RETURN(&work_dbuff, (uint8_t) (type | CBOR_2_BYTE));
    FR_DBUFF_IN_MEMCPY_RETURN(&work_dbuff, value, 2);
    goto done;
  }

  if (data < (((uint64_t) 1) << 32)) {
    fr_nbo_from_uint32(value, data);

    FR_DBUFF_IN_BYTES_RETURN(&work_dbuff, (uint8_t) (type | CBOR_4_BYTE));
    FR_DBUFF_IN_MEMCPY_RETURN(&work_dbuff, value, 4);
    goto done;
  }

  fr_nbo_from_uint64(value, data);

  /*
   *  Has to be 8 bytes.
   */
  FR_DBUFF_IN_BYTES_RETURN(&work_dbuff, type | CBOR_8_BYTE);
  FR_DBUFF_IN_MEMCPY_RETURN(&work_dbuff, value, 8);

done:
  return fr_dbuff_set(dbuff, &work_dbuff);
}

#define cbor_encode_array(_dbuff, _size) cbor_encode_integer(_dbuff, CBOR_ARRAY, _size)

#define cbor_encode_tag(_dbuff, _tag) cbor_encode_integer(_dbuff, CBOR_TAG, _tag)

/*
 *  Make many things easier
 */
#define return_slen return FR_DBUFF_ERROR_OFFSET(slen, fr_dbuff_used(&work_dbuff))

/*
 *  Octets is length + data
 */
static ssize_t cbor_encode_octets(fr_dbuff_t *dbuff, uint8_t const *data, size_t data_len)
{
  fr_dbuff_t  work_dbuff = FR_DBUFF(dbuff);
  ssize_t slen;

  slen = cbor_encode_integer(&work_dbuff, CBOR_OCTETS, data_len);
  if (slen <= 0) return_slen;

  if (data_len > 0) FR_DBUFF_IN_MEMCPY_RETURN(&work_dbuff, data, data_len);

  return fr_dbuff_set(dbuff, &work_dbuff);
}

static ssize_t cbor_encode_int64(fr_dbuff_t *dbuff, int64_t neg)
{
  fr_dbuff_t  work_dbuff = FR_DBUFF(dbuff);
  ssize_t slen;

  if (neg >= 0) {
    slen = cbor_encode_integer(&work_dbuff, CBOR_INTEGER, neg);
  } else {
    uint64_t data;

    neg++;
    data = -neg;
    slen = cbor_encode_integer(&work_dbuff, CBOR_NEGATIVE, data);
  }
  if (slen <= 0) return_slen;

  return fr_dbuff_set(dbuff, &work_dbuff);
}

#define cbor_encode_key cbor_encode_int64

/** Encode CBOR
 *
 *  Values 0..23 can be encoded in place.  Other values can be encoded using the closest smallest integer
 */
ssize_t fr_cbor_encode_value_box(fr_dbuff_t *dbuff, fr_value_box_t *vb)
{
  fr_dbuff_t  work_dbuff = FR_DBUFF(dbuff);
  uint8_t   type = CBOR_INTEGER;
  uint64_t  data;
  int64_t   neg;
  ssize_t   slen;
  uint8_t   const *p, *end;

  switch (vb->type) {
  case FR_TYPE_BOOL:
    /*
     *  One byte of FLOAT (i.e. special value), and the boolean as a "simple value".
     */
    FR_DBUFF_IN_BYTES_RETURN(&work_dbuff, (uint8_t) ((CBOR_FLOAT << 5) | (20 + vb->vb_bool)));
    break;

  case FR_TYPE_UINT8:
    data = vb->vb_uint8;
    goto encode_int;

  case FR_TYPE_UINT16:
    data = vb->vb_uint16;
    goto encode_int;

  case FR_TYPE_UINT32:
    data = vb->vb_uint32;
    goto encode_int;

  case FR_TYPE_UINT64:
    data = vb->vb_uint64;
    goto encode_int;

  /*
   *  Negative numbers.
   */
  case FR_TYPE_INT8:
    neg = vb->vb_int8;
    goto encode_neg;

  case FR_TYPE_INT16:
    neg = vb->vb_int16;
    goto encode_neg;

  case FR_TYPE_INT32:
    neg = vb->vb_int32;
    goto encode_neg;

  case FR_TYPE_INT64:
    neg = vb->vb_int64;
  encode_neg:
    if (neg >= 0) {
      type = CBOR_INTEGER;
      data = neg;
      goto encode_int;
    }

    /*
     *  convert -1..-2^63 to 0..-(2^63-1)
     *  and then it fits into a positive integer.
     */
    neg++;
    data = -neg;

  encode_int:
    return cbor_encode_integer(dbuff, type, data);

  case FR_TYPE_OCTETS:
    return cbor_encode_octets(dbuff, vb->vb_octets, vb->vb_length);

  case FR_TYPE_STRING:
    slen = cbor_encode_integer(&work_dbuff, CBOR_STRING, vb->vb_length);
    if (slen <= 0) return_slen;

    if (vb->vb_length) FR_DBUFF_IN_MEMCPY_RETURN(&work_dbuff, vb->vb_strvalue, vb->vb_length);
    break;

    /*
     *  More complex data types are represented by type "tag", followed by a tag number.  The
     *  actual data is then encoded as the next item after the tag.
     */
  case FR_TYPE_ETHERNET:
    slen = cbor_encode_tag(&work_dbuff, cbor_type_to_tag[vb->type]);
    if (slen <= 0) return_slen;

    slen = cbor_encode_octets(&work_dbuff, vb->vb_ether, sizeof(vb->vb_ether));
    if (slen <= 0) return_slen;
    break;

    /*
     *  Tag 1, with integer seconds since epoch.
     *
     *  @todo - if the input has time resolution, then save it in that format.
     *
     *  RFC 9581 Section 3.
     *
     *  A tag with key 1001, and then: a map with required key 1 (integer epoch seconds) and
     *  optional key -3 (milliseconds), -6 (microseconds), or -9 (integer nanoseconds).
     *
     *  For the encoder, there are a ton of different formats for dates, and we shouldn't
     *  bother to parse them all. :(
     */
  case FR_TYPE_DATE:
    slen = cbor_encode_tag(&work_dbuff, cbor_type_to_tag[vb->type]);
    if (slen <= 0) return_slen;

    neg = fr_unix_time_to_sec(vb->vb_date);
    slen = cbor_encode_int64(&work_dbuff, neg);
    if (slen <= 0) return_slen;
    break;

    /*
     *  RFC 9581 Section 4.
     *
     *  A tag with key 1002, and then: a map with required key 1 (integer seconds) and
     *  optional key -3 (milliseconds), -6 (microseconds), or -9 (integer nanoseconds).
     */
  case FR_TYPE_TIME_DELTA:
    slen = cbor_encode_tag(&work_dbuff, cbor_type_to_tag[vb->type]);
    if (slen <= 0) return_slen;

    neg = fr_time_delta_unwrap(vb->vb_time_delta) % NSEC;

    slen = cbor_encode_integer(&work_dbuff, CBOR_MAP, 1 + (neg != 0));
    if (slen <= 0) return_slen;

    /*
     *  1: seconds
     */
    slen = cbor_encode_key(&work_dbuff, 1);
    if (slen <= 0) return_slen;

    slen = cbor_encode_int64(&work_dbuff, fr_time_delta_to_sec(vb->vb_time_delta));
    if (slen <= 0) return_slen;

    /*
     *  -9: nanoseconds
     */
    if (neg) {
      slen = cbor_encode_key(&work_dbuff, -9);
      if (slen <= 0) return_slen;

      slen = cbor_encode_int64(&work_dbuff, neg);
      if (slen <= 0) return_slen;
    }
    break;

    /*
     *  RFC 9164, Section 3.3
     *
     *
     *  tag=IPv4 + address + optional (prefix + scope)
     */
  case FR_TYPE_IPV4_ADDR:
    slen = cbor_encode_tag(&work_dbuff, cbor_type_to_tag[vb->type]);
    if (slen <= 0) return_slen;

    if (vb->vb_ip.scope_id != 0) {
      FR_DBUFF_IN_BYTES_RETURN(&work_dbuff, (uint8_t) ((CBOR_ARRAY << 5) | 3));

    }

    slen = cbor_encode_octets(&work_dbuff, (uint8_t const *) &vb->vb_ipv4addr, 4);
    if (slen <= 0) return_slen;

    if (vb->vb_ip.scope_id == 0) break;

    slen = cbor_encode_integer(&work_dbuff, CBOR_INTEGER, (uint8_t) 32);
    if (slen <= 0) return_slen;

    slen = cbor_encode_integer(&work_dbuff, CBOR_INTEGER, vb->vb_ip.scope_id);
    if (slen <= 0) return_slen;
    break;

    /*
     *  RFC 9164, Section 3.2
     *
     *  tag=IPv6 + address + optional (prefix + scope)
     */
  case FR_TYPE_IPV6_ADDR:
    slen = cbor_encode_tag(&work_dbuff, cbor_type_to_tag[vb->type]);
    if (slen <= 0) return_slen;

    if (vb->vb_ip.scope_id != 0) {
      FR_DBUFF_IN_BYTES_RETURN(&work_dbuff, (uint8_t) ((CBOR_ARRAY << 5) | 3));
    }

    slen = cbor_encode_octets(&work_dbuff, (uint8_t const *) &vb->vb_ipv6addr, 16);
    if (slen <= 0) return_slen;

    if (vb->vb_ip.scope_id == 0) break;

    slen = cbor_encode_integer(&work_dbuff, CBOR_INTEGER, (uint8_t) 128);
    if (slen <= 0) return_slen;

    slen = cbor_encode_integer(&work_dbuff, CBOR_INTEGER, vb->vb_ip.scope_id);
    if (slen <= 0) return_slen;
    break;

    /*
     *  RFC 9164, Section 3.3
     *
     *  tag=IPv4 + array(prefix-length, address)
     */
  case FR_TYPE_IPV4_PREFIX:
    slen = cbor_encode_tag(&work_dbuff, cbor_type_to_tag[vb->type]);
    if (slen <= 0) return_slen;

    slen = cbor_encode_array(&work_dbuff, 2);
    if (slen <= 0) return_slen;

    slen = cbor_encode_integer(&work_dbuff, CBOR_INTEGER, vb->vb_ip.prefix);
    if (slen <= 0) return_slen;

    p = (uint8_t const *) &vb->vb_ipv4addr;
    end = p + 3;

    /*
     *  RFC 9164 Section 4.2 - Drop lower octets which are all zero.
     *
     *  If this results in a zero-length string, so be it.
     *
     *  Note also that "There is no relationship between the number of bytes omitted and the
     *  prefix length."
     */
    do {
      if (*end != 0) break;

      end--;
    } while (end != p);

    slen = cbor_encode_octets(&work_dbuff, p, (end - p) + (*end != 0));
    if (slen <= 0) return_slen;
    break;

    /*
     *  RFC 9164, Section 3.2
     *
     *  tag=IPv6 + array(prefix-length, address)
     */
  case FR_TYPE_IPV6_PREFIX:
    slen = cbor_encode_tag(&work_dbuff, cbor_type_to_tag[vb->type]);
    if (slen <= 0) return_slen;

    slen = cbor_encode_array(&work_dbuff, 2);
    if (slen <= 0) return_slen;

    slen = cbor_encode_integer(&work_dbuff, CBOR_INTEGER, vb->vb_ip.prefix);
    if (slen <= 0) return_slen;

    p = (uint8_t const *) &vb->vb_ipv6addr;
    end = p + 15;

    /*
     *  RFC 9164 Section 4.2 - Drop lower octets which are all zero.
     *
     *  If this results in a zero-length string, so be it.
     *
     *  Note also that "There is no relationship between the number of bytes omitted and the
     *  prefix length."
     */
    do {
      if (*end != 0) break;

      end--;
    } while (end != p);

    slen = cbor_encode_octets(&work_dbuff, p, (end - p) + (*end != 0));
    if (slen <= 0) return_slen;

    break;

  case FR_TYPE_FLOAT32:
    FR_DBUFF_IN_BYTES_RETURN(&work_dbuff, (uint8_t) ((CBOR_FLOAT << 5) | CBOR_4_BYTE));
    FR_DBUFF_IN_MEMCPY_RETURN(&work_dbuff, (uint8_t const *) &vb->vb_float32, sizeof(vb->vb_float32));
    break;

  case FR_TYPE_FLOAT64:
    FR_DBUFF_IN_BYTES_RETURN(&work_dbuff, (uint8_t) ((CBOR_FLOAT << 5) | CBOR_8_BYTE));
    FR_DBUFF_IN_MEMCPY_RETURN(&work_dbuff, (uint8_t const *) &vb->vb_float64, sizeof(vb->vb_float64));
    break;

  case FR_TYPE_GROUP:
    /*
     *  Zero-length array.
     */
    if (fr_value_box_list_num_elements(&vb->vb_group) == 0) {
      FR_DBUFF_IN_BYTES_RETURN(&work_dbuff, (uint8_t) ((CBOR_ARRAY << 5) | 0));
      break;
    }

    /*
     *  The value is array(children)
     */
    slen = cbor_encode_integer(&work_dbuff, CBOR_ARRAY,
             fr_value_box_list_num_elements(&vb->vb_group));
    if (slen <= 0) return_slen;


    fr_value_box_list_foreach(&vb->vb_group, child) {
      slen = fr_cbor_encode_value_box(&work_dbuff, child);
      if (slen <= 0) return_slen;
    }
    break;


  default:
    fr_strerror_printf("Invalid data type %s for cbor encoding", fr_type_to_str(vb->type));
    return -1;
  }

  return fr_dbuff_set(dbuff, &work_dbuff);
}


static ssize_t cbor_decode_integer(uint64_t *out, uint8_t info, fr_dbuff_t *dbuff)
{
  fr_dbuff_t work_dbuff = FR_DBUFF(dbuff);

  if (info < 24) {
    *out = info;
    return 0;
  }

  if (info == CBOR_1_BYTE) {
    uint8_t value;

    FR_DBUFF_OUT_RETURN(&value, &work_dbuff);
    *out = value;
    goto done;
  }

  if (info == CBOR_2_BYTE) {
    uint16_t value;

    FR_DBUFF_OUT_RETURN(&value, &work_dbuff);
    *out = value;
    goto done;
  }

  if (info == CBOR_4_BYTE) {
    uint32_t value;

    FR_DBUFF_OUT_RETURN(&value, &work_dbuff);
    *out = value;
    goto done;
  }

  if (info == CBOR_8_BYTE) {
    uint64_t value;

    FR_DBUFF_OUT_RETURN(&value, &work_dbuff);
    *out = value;
    goto done;
  }

  /*
   *  28 and greater are invalid according to the RFCs.
   */
  if (info > CBOR_8_BYTE) return -1;

done:
  return fr_dbuff_set(dbuff, &work_dbuff);
}

static ssize_t cbor_decode_count(uint64_t *out, int expected, fr_dbuff_t *dbuff)
{
  fr_dbuff_t work_dbuff = FR_DBUFF(dbuff);
  uint8_t major, info;
  ssize_t slen;

  FR_DBUFF_OUT_RETURN(&major, &work_dbuff);

  info = major & 0x1f;
  major >>= 5;

  if (major != expected) {
    fr_strerror_printf("Expected cbor type '%s', got unexpected type %d ",
           cbor_type_to_str[expected], major);
    return -1;
  }

  slen = cbor_decode_integer(out, info, &work_dbuff);
  if (slen < 0) return_slen;

  return fr_dbuff_set(dbuff, &work_dbuff);
}

typedef ssize_t (*cbor_decode_type_t)(TALLOC_CTX *ctx, fr_value_box_t *vb, fr_dbuff_t *dbuff);

static ssize_t cbor_decode_octets_memcpy(uint8_t *dst, size_t dst_min, size_t dst_max, fr_dbuff_t *dbuff)
{
  fr_dbuff_t work_dbuff = FR_DBUFF(dbuff);
  ssize_t slen;
  uint64_t value = 0;

  slen = cbor_decode_count(&value, CBOR_OCTETS, &work_dbuff);
  if (slen < 0) return_slen;

  if (value < dst_min) {
    fr_strerror_printf("Invalid length for data - expected at least %zu got %" PRIu64, dst_min, value);
    return -1;
  }

  if (value > dst_max) {
    fr_strerror_printf("Invalid length for data - expected no more than %zu got %" PRIu64, dst_max, value);
    return -1;
  }

  FR_DBUFF_OUT_MEMCPY_RETURN(dst, &work_dbuff, value);

  return fr_dbuff_set(dbuff, &work_dbuff);
}

#if 0
static ssize_t *cbor_decode_octets_memdup(TALLOC_CTX *ctx, uint8_t **out, fr_dbuff_t *dbuff)
{
  fr_dbuff_t work_dbuff = FR_DBUFF(dbuff);
  ssize_t slen;
  uint64_t value;
  uint8_t *ptr;

  slen = cbor_decode_count(&value, CBOR_OCTETS, &work_dbuff);
  if (slen < 0) return_slen;

  if (value > (1 << 20)) {
    fr_strerror_printf("cbor data string is too long (%" PRIu64 ")", value);
    return -1;
  }

  ptr = talloc_array(ctx, uint8_t, value);
  if (!ptr) {
    fr_strerror_const("Out of memory");
    return -1;
  }

  FR_DBUFF_OUT_MEMCPY_RETURN(ptr, &work_dbuff, value);
  *out = ptr;

  return fr_dbuff_set(dbuff, &work_dbuff);
}
#endif

static ssize_t cbor_decode_ethernet(UNUSED TALLOC_CTX *ctx, fr_value_box_t *vb, fr_dbuff_t *dbuff)
{
  return cbor_decode_octets_memcpy(vb->vb_ether, sizeof(vb->vb_ether), sizeof(vb->vb_ether), dbuff);
}

static ssize_t cbor_decode_ipv4_addr(UNUSED TALLOC_CTX *ctx, fr_value_box_t *vb, fr_dbuff_t *dbuff)
{
  fr_dbuff_t work_dbuff = FR_DBUFF(dbuff);
  ssize_t slen;
  uint8_t header;
  size_t count = 0;
  uint64_t value = 0;

  FR_DBUFF_EXTEND_LOWAT_OR_RETURN(&work_dbuff, 1);

  header = *fr_dbuff_current(&work_dbuff);
  if ((header >> 5) == CBOR_ARRAY) {
    count = header & 0x1f;

    if ((count != 2) && (count != 3)) {
      fr_strerror_printf("Invalid IPv4 interface - expected array of 2-3 elements, got %02x",
             header);
      return -1;
    }

    fr_dbuff_advance(&work_dbuff, 1);
  }

  vb->vb_ip.prefix = 32;

  /*
   *  Get the IP address.
   */
  slen = cbor_decode_octets_memcpy((uint8_t *) &vb->vb_ipv4addr,
           sizeof(vb->vb_ipv4addr),
           sizeof(vb->vb_ipv4addr), &work_dbuff);
  if (slen <= 0) return_slen;

  if (!count) return fr_dbuff_set(dbuff, &work_dbuff);

  slen = cbor_decode_count(&value, CBOR_INTEGER, &work_dbuff);
  if (slen <= 0) return_slen;

  if (value != 32) {
    fr_strerror_printf("Invalid IPv4 address - expected prefix = 32 got %" PRIu64, value);
    return -fr_dbuff_used(&work_dbuff);
  }

  if (count == 2) return fr_dbuff_set(dbuff, &work_dbuff);

  /*
   *  Get the scope ID
   */
  slen = cbor_decode_count(&value, CBOR_INTEGER, &work_dbuff);
  if (slen <= 0) return_slen;

  vb->vb_ip.scope_id = value;

  return fr_dbuff_set(dbuff, &work_dbuff);
}

static ssize_t cbor_decode_ipv6_addr(UNUSED TALLOC_CTX *ctx, fr_value_box_t *vb, fr_dbuff_t *dbuff)
{
  fr_dbuff_t work_dbuff = FR_DBUFF(dbuff);
  ssize_t slen;
  uint8_t header;
  size_t count = 0;
  uint64_t value = 0;

  FR_DBUFF_EXTEND_LOWAT_OR_RETURN(&work_dbuff, 1);

  header = *fr_dbuff_current(&work_dbuff);
  if ((header >> 5) == CBOR_ARRAY) {
    count = header & 0x1f;

    if ((count != 2) && (count != 3)) {
      fr_strerror_printf("Invalid IPv4 interface - expected array of 2-3 elements, got %02x",
             header);
      return -1;
    }

    fr_dbuff_advance(&work_dbuff, 1);
  }

  vb->vb_ip.prefix = 128;

  /*
   *  Get the IP address.
   */
  slen = cbor_decode_octets_memcpy((uint8_t *) &vb->vb_ipv6addr,
           sizeof(vb->vb_ipv6addr),
           sizeof(vb->vb_ipv6addr), &work_dbuff);

  if (slen <= 0) return_slen;

  if (!count) return fr_dbuff_set(dbuff, &work_dbuff);

  slen = cbor_decode_count(&value, CBOR_INTEGER, &work_dbuff);
  if (slen <= 0) return_slen;

  if (value != 128) {
    fr_strerror_printf("Invalid IPv6 address - expected prefix = 128 got %" PRIu64, value);
    return -fr_dbuff_used(&work_dbuff);
  }

  vb->vb_ip.prefix = value;

  if (count == 2) return fr_dbuff_set(dbuff, &work_dbuff);

  /*
   *  Get the scope ID
   */
  slen = cbor_decode_count(&value, CBOR_INTEGER, &work_dbuff);
  if (slen <= 0) return_slen;

  vb->vb_ip.scope_id = value;

  return fr_dbuff_set(dbuff, &work_dbuff);
}

static ssize_t cbor_decode_ipv4_prefix(UNUSED TALLOC_CTX *ctx, fr_value_box_t *vb, fr_dbuff_t *dbuff)
{
  fr_dbuff_t work_dbuff = FR_DBUFF(dbuff);
  ssize_t slen;
  uint8_t header;
  uint64_t value = 0;
  uint8_t buffer[sizeof(vb->vb_ipv4addr)];

  FR_DBUFF_OUT_RETURN(&header, &work_dbuff);

  if (header != ((CBOR_ARRAY << 5) | 2)) {
    fr_strerror_printf("Invalid IPv4 prefix - expected array of 2 elements, got %02x",
           header);
    return -1;
  }

  slen = cbor_decode_count(&value, CBOR_INTEGER, &work_dbuff);
  if (slen <= 0) return_slen;

  if (value > 32) {
    fr_strerror_printf("Invalid IPv4 prefix - expected prefix < 32, got %" PRIu64, value);
    return -1;
  }

  /*
   *  RFC 9164 Section 4.3 - Trailing bytes of zero are omitted, so we
   *  first copy the data to a fixed-sized buffer which was
   *  zeroed out, and then (@todo) also check that unused bits in
   *  the last byte are all zero.
   */
  memset(buffer, 0, sizeof(buffer));

  slen = cbor_decode_octets_memcpy(buffer, 0, sizeof(buffer), &work_dbuff);
  if (slen <= 0) return_slen;

  memcpy((uint8_t *) &vb->vb_ipv4addr, buffer, sizeof(vb->vb_ipv4addr));
  vb->vb_ip.prefix = value;

  return fr_dbuff_set(dbuff, &work_dbuff);
}

static ssize_t cbor_decode_ipv6_prefix(UNUSED TALLOC_CTX *ctx, fr_value_box_t *vb, fr_dbuff_t *dbuff)
{
  fr_dbuff_t work_dbuff = FR_DBUFF(dbuff);
  ssize_t slen;
  uint8_t header;
  uint64_t value = 0;
  uint8_t buffer[sizeof(vb->vb_ipv6addr)];

  FR_DBUFF_OUT_RETURN(&header, &work_dbuff);

  if (header != ((CBOR_ARRAY << 5) | 2)) {
    fr_strerror_printf("Invalid IPv6 prefix - expected array of 2 elements, got %02x",
           header);
    return -1;
  }

  slen = cbor_decode_count(&value, CBOR_INTEGER, &work_dbuff);
  if (slen <= 0) return_slen;

  if (value > 128) {
    fr_strerror_printf("Invalid IPv6 prefix - expected prefix < 128, got %" PRIu64, value);
    return -1;
  }

  /*
   *  RFC 9164 Section 4.3 - Trailing bytes of zero are omitted, so we
   *  first copy the data to a fixed-sized buffer which was
   *  zeroed out, and then (@todo) also check that unused bits in
   *  the last byte are all zero.
   */
  memset(buffer, 0, sizeof(buffer));

  slen = cbor_decode_octets_memcpy(buffer, 0, sizeof(buffer), &work_dbuff);
  if (slen <= 0) return_slen;

  memcpy((uint8_t *) &vb->vb_ipv6addr, buffer, sizeof(vb->vb_ipv6addr));
  vb->vb_ip.prefix = value;

  return fr_dbuff_set(dbuff, &work_dbuff);
}

static ssize_t cbor_decode_int64(int64_t *out, fr_dbuff_t *dbuff, fr_type_t type)
{
  fr_dbuff_t work_dbuff = FR_DBUFF(dbuff);
  ssize_t slen;
  uint8_t major, info;
  uint64_t value = 0;
  int64_t neg;

  FR_DBUFF_OUT_RETURN(&major, &work_dbuff);

  info = major & 0x1f;
  major >>= 5;

  switch (major) {
  case CBOR_INTEGER:
    slen = cbor_decode_integer(&value, info, &work_dbuff);
    if (slen < 0) return_slen;

    if (value >= ((uint64_t) 1) << 63) { /* equal! */
    invalid:
      fr_strerror_printf("cbor value is too large for output data type %s",
             fr_type_to_str(type));
      return -1;
    }

    *out = value;
    break;

  case CBOR_NEGATIVE:
    slen = cbor_decode_integer(&value, info, &work_dbuff);
    if (slen < 0) return_slen;

    if (value >= ((uint64_t) 1) << 63) goto invalid; /* greater than! */

    /*
     *  Convert 0..(2^63-1) into -0..-(2^63-1)
     *  then conver to -1..-(2^63)
     */
    neg = -value;
    neg--;

    *out = neg;
    break;

  default:
    fr_strerror_printf("cbor data contains invalid content %d for expected data type %s",
           major, fr_type_to_str(type));
    return -1;
  }

  return fr_dbuff_set(dbuff, &work_dbuff);

}

static ssize_t cbor_decode_date(UNUSED TALLOC_CTX *ctx, fr_value_box_t *vb, fr_dbuff_t *dbuff)
{
  fr_dbuff_t work_dbuff = FR_DBUFF(dbuff);
  ssize_t slen;
  int64_t neg;

  slen = cbor_decode_int64(&neg, &work_dbuff, FR_TYPE_DATE);
  if (slen <= 0) return_slen;

  vb->vb_date = fr_unix_time_from_sec(neg);

  return fr_dbuff_set(dbuff, &work_dbuff);
}

/*
 *  Tag 1002, followed by map of at least 2 elements
 *  key 1: seconds
 *  key -9: nanoseconds
 */
static ssize_t cbor_decode_time_delta(UNUSED TALLOC_CTX *ctx, fr_value_box_t *vb, fr_dbuff_t *dbuff)
{
  fr_dbuff_t work_dbuff = FR_DBUFF(dbuff);
  uint64_t count;
  ssize_t slen;
  int64_t key, seconds, fraction, scale;

  slen = cbor_decode_count(&count, CBOR_MAP, &work_dbuff);
  if (slen < 0) return_slen;

  if (!count || (count > 2)) {
    fr_strerror_printf("Unexpected count %" PRIu64"  for time_delta, expected map of 1-2 elements", count);
    return -1;
  }

  key = seconds = fraction = 0;

  /*
   *  Expect key 1:seconds
   */
  slen = cbor_decode_int64(&key, &work_dbuff, FR_TYPE_TIME_DELTA);
  if (slen < 0) return_slen;

  if (key != 1) {
    fr_strerror_printf("Unexpected key %" PRIi64 " for time_delta, expected key 1", key);
    return -1;
  }

  slen = cbor_decode_int64(&seconds, &work_dbuff, FR_TYPE_TIME_DELTA);
  if (slen < 0) return_slen;

  if (count > 1) {
    slen = cbor_decode_int64(&key, &work_dbuff, FR_TYPE_TIME_DELTA);
    if (slen < 0) return_slen;

    switch (key) {
    case -3:
      scale = MSEC;
      break;

    case -6:
      scale = USEC;
      break;

    case -9:
      scale = NSEC;
      break;

    default:
      fr_strerror_printf("Unsupported time_delta key %" PRIi64, key);
      return -fr_dbuff_used(&work_dbuff); /* point to actual key? */

    }

    slen = cbor_decode_int64(&fraction, &work_dbuff, FR_TYPE_TIME_DELTA);
    if (slen < 0) return_slen;

    if ((fraction < 0) || (fraction > scale)) fraction = 0;
  } else {
    scale = NSEC;
    fraction = 0;
  }

  if (seconds > (INT64_MAX / scale)) {
    vb->vb_time_delta = fr_time_delta_max();

  } else if (seconds < (INT64_MIN / scale)) {
    vb->vb_time_delta = fr_time_delta_min();

  } else {
    seconds *= scale;

    if (seconds < 0) {
      seconds -= fraction;
    } else {
      seconds += fraction;
    }

    vb->vb_time_delta = fr_time_delta_wrap(seconds);
  }

  return fr_dbuff_set(dbuff, &work_dbuff);
}


static cbor_decode_type_t cbor_decode_type[FR_TYPE_MAX] = {
  [FR_TYPE_ETHERNET] = cbor_decode_ethernet,

  [FR_TYPE_DATE] = cbor_decode_date,
  [FR_TYPE_TIME_DELTA] = cbor_decode_time_delta,

  [FR_TYPE_IPV4_ADDR] = cbor_decode_ipv4_addr,
  [FR_TYPE_IPV6_ADDR] = cbor_decode_ipv6_addr,

  [FR_TYPE_IPV4_PREFIX] = cbor_decode_ipv4_prefix,
  [FR_TYPE_IPV6_PREFIX] = cbor_decode_ipv6_prefix,
};

/*
 *  @todo - fr_cbor_encode_pair_list().  And then if we have da->flags.array, we encode the _value_ as an
 *  array of indeterminate length.  This is a little bit of a special case, but not terrible.
 */
ssize_t fr_cbor_decode_value_box(TALLOC_CTX *ctx, fr_value_box_t *vb, fr_dbuff_t *dbuff,
         fr_type_t type, fr_dict_attr_t const *enumv, bool tainted)
{
  fr_dbuff_t work_dbuff = FR_DBUFF(dbuff);
  bool indefinite;
  uint8_t major, info;
  ssize_t slen;
  int64_t neg;
  uint64_t value;
  uint8_t *ptr;

  FR_DBUFF_OUT_RETURN(&major, &work_dbuff);

  if (type == FR_TYPE_NULL) {
    type = cbor_guess_type(&work_dbuff, false);
    if (type == FR_TYPE_NULL) {
      fr_strerror_const("Unable to determine data type from cbor");
      return -1;
    }
  }

  fr_value_box_init(vb, type, enumv, tainted);

  info = major & 0x1f;
  major >>= 5;

  /*
   *  Invalid combinations.
   */
  if (((info >= 28) && (info <= 30)) ||
      ((info == 31) && ((major == 0) || (major == 1) || (major == 6)))) {
    fr_strerror_const("Invalid cbor data - input is not 'well formed'");
    return -1;
  }

  switch (major) {
  case CBOR_STRING:
    if (type != FR_TYPE_STRING) {
    mismatch:
      fr_strerror_printf("cbor data contains invalid content %d for expected data type %s",
             major, fr_type_to_str(type));
      return -1;
    }

    if (info == 31) {
    no_chunks:
      fr_strerror_const("Chunked strings are not supported");
      return -1;
    }


    /*
     *  @todo - undefinite length strings.  Which are really "chunked" strings.
     */
    slen = cbor_decode_integer(&value, info, &work_dbuff);
    if (slen < 0) return_slen;

    /*
     *  A little bit of sanity check.
     */
    if (value > (1 << 20)) {
      fr_strerror_printf("cbor data string is too long (%" PRIu64 ")", value);
      return -1;
    }

    ptr = talloc_array(ctx, uint8_t, value + 1);
    if (!ptr) {
      fr_strerror_const("Out of memory");
      return -1;
    }
    talloc_set_type(ptr, char);
    if (value) FR_DBUFF_OUT_MEMCPY_RETURN(ptr, &work_dbuff, value);
    ptr[value] = '\0';

    fr_value_box_strdup_shallow(vb, NULL, (char const *) ptr, tainted);

    break;

  case CBOR_OCTETS:
    if (type != FR_TYPE_OCTETS) goto mismatch;

    if (info == 31) goto no_chunks;

    /*
     *  @todo - indefinite length octet strings.  Which are really "chunked" octet strings.
     */
    slen = cbor_decode_integer(&value, info, &work_dbuff);
    if (slen < 0) return_slen;

    /*
     *  A little bit of sanity check.
     */
    if (value > (1 << 20)) {
      fr_strerror_printf("cbor data string is too long (%" PRIu64 ")", value);
      return -1;
    }

    ptr = talloc_array(ctx, uint8_t, value);
    if (!ptr) {
      fr_strerror_const("Out of memory");
      return -1;
    }

    fr_value_box_memdup_shallow(vb, NULL, (uint8_t const *) ptr, value, false); /* tainted? */

    if (value) FR_DBUFF_OUT_MEMCPY_RETURN(ptr, &work_dbuff, value);
    break;

  case CBOR_INTEGER:
    slen = cbor_decode_integer(&value, info, &work_dbuff);
    if (slen < 0) return_slen;

    switch (type) {
    case FR_TYPE_BOOL:
      if (value > 1) goto invalid_bool;
      vb->vb_bool = value;
      break;

    case FR_TYPE_UINT8:
      if (value > UINT8_MAX) {
      invalid:
        fr_strerror_printf("cbor value is too large for output data type %s",
               fr_type_to_str(type));
        return -1;
      }
      vb->vb_uint8 = value;
      break;

    case FR_TYPE_UINT16:
      if (value > UINT16_MAX) goto invalid;
      vb->vb_uint16 = value;
      break;

    case FR_TYPE_UINT32:
      if (value > UINT32_MAX) goto invalid;
      vb->vb_uint32 = value;
      break;

    case FR_TYPE_UINT64:
      vb->vb_uint64 = value;
      break;

    case FR_TYPE_INT8:
      if (value > INT8_MAX) goto invalid;
      vb->vb_int8 = value;
      break;

    case FR_TYPE_INT16:
      if (value > INT16_MAX) goto invalid;
      vb->vb_int16 = value;
      break;

    case FR_TYPE_INT32:
      if (value > INT32_MAX) goto invalid;
      vb->vb_int32 = value;
      break;

    case FR_TYPE_INT64:
      if (value > INT64_MAX) goto invalid;
      vb->vb_int64 = value;
      break;

    default:
    integer_type_mismatch:
      fr_strerror_printf("Unexpected cbor type 'integer' when decoding data type %s",
             fr_type_to_str(type));
      return -1;
    }
    break;

  case CBOR_NEGATIVE:
    slen = cbor_decode_integer(&value, info, &work_dbuff);
    if (slen < 0) return_slen;

    /*
     *  Signed numbers only go down to -2^63
     *  so value must be less than 2^63
     */
    if (value >= ((uint64_t) 1) << 63) goto invalid;

    /*
     *  Convert 0..(2^63-1) into -0..-(2^63-1)
     *  then conver to -1..-(2^63)
     */
    neg = -value;
    neg--;

    switch (type) {
    case FR_TYPE_INT8:
      if (neg < INT8_MIN) goto invalid;
      vb->vb_int8 = neg;
      break;

    case FR_TYPE_INT16:
      if (neg < INT16_MIN) goto invalid;
      vb->vb_int16 = neg;
      break;

    case FR_TYPE_INT32:
      if (neg < INT32_MIN) goto invalid;
      vb->vb_int32 = neg;
      break;

    case FR_TYPE_INT64:
      vb->vb_int64 = neg;
      break;

    default:
      goto integer_type_mismatch;
    }
    break;

  case CBOR_FLOAT:
    /*
     *  Simple values.  See RFC 8489 Section 3.3.
     *
     *  20 - false
     *  21 - true
     *  22 - NULL
     */
    if (info < 24) {
      switch (type) {
      case FR_TYPE_BOOL:
        if (info == 20) {
          vb->vb_bool = false;
          break;
        }

        if (info == 21) {
          vb->vb_bool = true;
          break;
        }

      invalid_bool:
        fr_strerror_printf("Invalid cbor - boolean is not encoded as 'true' or 'false'");
        return -fr_dbuff_used(&work_dbuff);

      case FR_TYPE_OCTETS:
      case FR_TYPE_STRING:
      case FR_TYPE_TLV:
      case FR_TYPE_VENDOR:
      case FR_TYPE_GROUP:
      case FR_TYPE_STRUCT:
        /*
         *  Be a little forgiving.  22 is NULL, so we treat that as "nothing".
         *
         *  i.e. empty string, empty set, etc.
         */
        if (info == 22) break;

        FALL_THROUGH;

      default:
        fr_strerror_printf("Invalid cbor - unexpected 'simple value' %u", info);
        return -fr_dbuff_used(&work_dbuff);
      }
      break;
    }

    /*
     *  Or as one-byte integers.
     */
    if (info == CBOR_1_BYTE) {
      uint8_t data;

      FR_DBUFF_OUT_RETURN(&data, &work_dbuff);

      switch (type) {
      case FR_TYPE_FLOAT32:
        vb->vb_float32 = data;
        break;

      case FR_TYPE_FLOAT64:
        vb->vb_float64 = data;
        break;

      default:
      float_type_mismatch:
        fr_strerror_printf("Unexpected cbor type 'float' when decoding data type %s",
               fr_type_to_str(type));
        return -1;
      }

      break;
    }

    /*
     *  We don't support float16
     */

    if (info == CBOR_4_BYTE) {
      float data;

      FR_DBUFF_OUT_RETURN(&data, &work_dbuff);

      switch (type) {
      case FR_TYPE_FLOAT32:
        vb->vb_float32 = data;
        break;

      case FR_TYPE_FLOAT64:
        vb->vb_float64 = (double) data;
        break;

      default:
        goto float_type_mismatch;
      }

      break;
    }

    if (info == CBOR_8_BYTE) {
      double data;

      FR_DBUFF_OUT_RETURN(&data, &work_dbuff);

      switch (type) {
      case FR_TYPE_FLOAT32:
        vb->vb_float32 = data; /* maybe loses precision? */
        break;

      case FR_TYPE_FLOAT64:
        vb->vb_float64 = data;
        break;

      default:
        goto float_type_mismatch;
      }

      break;
    }

    /*
     *  24 is FLOAT16, which we don't support.
     *  31 is BREAK, which the caller should have checked for.
     */
    goto float_type_mismatch;

  case CBOR_TAG:
    /*
     *  We only support a limited number of tags.
     */
    slen = cbor_decode_integer(&value, info, &work_dbuff);
    if (slen < 0) return_slen;

    /*
     *  No tag defined for this data type, that's on us.
     */
    if (!cbor_type_to_tag[type]) {
      fr_strerror_printf("Unknown cbor tag %" PRIu64 " for expected data type %s",
             value, fr_type_to_str(type));
      return -fr_dbuff_used(&work_dbuff);
    }

    /*
     *  Wrong tag for this data type, that's on them.
     */
    if (cbor_type_to_tag[type] != value) {
      fr_strerror_printf("Invalid cbor tag %" PRIu64 " for expected data type %s",
             value, fr_type_to_str(type));
      return -fr_dbuff_used(&work_dbuff);
    }

    fr_value_box_init(vb, type, enumv, tainted);

    slen = cbor_decode_type[type](ctx, vb, &work_dbuff);
    if (slen < 0) return_slen;
    break;

  case CBOR_ARRAY:
    if (type != FR_TYPE_GROUP) goto invalid_type;

    /*
     *  Loop until done.
     */
    if (info == 31) {
      value = ~0;
      indefinite = true;

    } else {
      slen = cbor_decode_integer(&value, info, &work_dbuff);
      if (slen < 0) return_slen;

      indefinite = false;
    }

#ifdef STATIC_ANALYZER
    if (value > fr_dbuff_remaining(&work_dbuff)) return -1;
#endif

    /*
     *  Loop until we decode everything.  For simplicity, we handle indefinite and definite
     *  length arrays in the same loop.
     */
    for (/* nothing */; value > 0; value--) {
      uint8_t header;
      fr_value_box_t *child;

      /*
       *  Require at least one byte in the buffer.
       */
      FR_DBUFF_EXTEND_LOWAT_OR_RETURN(&work_dbuff, 1);

      /*
       *  Peek ahead for a break.
       */
      header = *fr_dbuff_current(&work_dbuff);
      if (header == 0xff) {
        if (!indefinite) {
          fr_strerror_const("Unexpected 'break' found in cbor data");
          return -fr_dbuff_used(&work_dbuff);
        }

        /*
         *  Done!
         */
        fr_dbuff_advance(&work_dbuff, 1);
        break;
      }

      child = fr_value_box_alloc(ctx, FR_TYPE_NULL, NULL);
      if (!child) {
        fr_strerror_const("Out of memory");
        return -fr_dbuff_used(&work_dbuff);
      }

      /*
       *  We have to decode at least one value.
       */
      slen = fr_cbor_decode_value_box(child, child, &work_dbuff, FR_TYPE_NULL, NULL, tainted);
      if (slen <= 0) {
        talloc_free(child);
        return_slen;
      }

      fr_value_box_list_insert_tail(&vb->vb_group, child);
    }
    break;

    /*
     *  These are not value-box types.
     */
  case CBOR_MAP:
  invalid_type:
    fr_strerror_printf("Invalid data type %s for cbor to value-box", fr_type_to_str(type));
    return -1;
  }

  return fr_dbuff_set(dbuff, &work_dbuff);
}

/** Encode a pair
 *
 */
ssize_t fr_cbor_encode_pair(fr_dbuff_t *dbuff, fr_pair_t *vp)
{
  fr_dbuff_t  work_dbuff = FR_DBUFF(dbuff);
  ssize_t   slen;
  fr_dict_attr_t const *parent;
  size_t    count;

  FR_DBUFF_IN_BYTES_RETURN(&work_dbuff, (uint8_t) ((CBOR_MAP << 5) | 1)); /* map of 1 item */

  /*
   *  Key is the attribute number.
   */
  slen = cbor_encode_integer(&work_dbuff, CBOR_INTEGER, vp->da->attr);
  if (slen <= 0) return_slen;

  /*
   *  Value is the actual value of the leaf, or the array of children.
   */
  switch (vp->vp_type) {
  case FR_TYPE_LEAF:
    slen = fr_cbor_encode_value_box(&work_dbuff, &vp->data);
    if (slen <= 0) return_slen;
    break;

    /*
     *  Groups reparent to the ref.
     */
  case FR_TYPE_GROUP:
    parent = fr_dict_attr_ref(vp->da);
    fr_assert(parent != NULL);
    goto encode_children;

    /*
     *  The only difference between TLV and VSA is that the children of VSA are all VENDORs.
     */
  case FR_TYPE_VENDOR:
  case FR_TYPE_VSA:
  case FR_TYPE_TLV:
    parent = vp->da;

    /*
     *  The value is array(children)
     */
encode_children:
    if (fr_pair_list_num_elements(&vp->vp_group) == 0) {
      FR_DBUFF_IN_BYTES_RETURN(&work_dbuff, (uint8_t) ((CBOR_FLOAT << 5) | 22)); /* NULL */
      break;
    }

    /*
     *  The groups, etc. may contain internal attributes.  We don't yet deal with those.
     */
    count = 0;
    fr_pair_list_foreach(&vp->vp_group, child) {
      if (child->da->parent != parent) continue;
      count++;
    }

    slen = cbor_encode_integer(&work_dbuff, CBOR_ARRAY, count);
    if (slen <= 0) return_slen;

    fr_pair_list_foreach(&vp->vp_group, child) {
      /*
       *  We don't allow changing dictionaries here.
       */
      if (child->da->parent != parent) continue;

      slen = fr_cbor_encode_pair(&work_dbuff, child);
      if (slen <= 0) return_slen;
    }
    break;

  /*
   *  @todo - struct, except if we hit the end of the struct, check if the next child is the child
   *  of the key?  That makes it all more annoying :(
   */

  default:
    fr_strerror_printf("Invalid data type %s for cbor encoding", fr_type_to_str(vp->vp_type));
    return -1;
  }

  return fr_dbuff_set(dbuff, &work_dbuff);
}

/** Guess the data type of the CBOR data.
 *
 *  We've parsed the attribute number, and found that we don't have a dictionary entry for it.  But rather
 *  than create an attribute of type octets, we try to guess the data type.
 */
static fr_type_t cbor_guess_type(fr_dbuff_t *dbuff, bool pair)
{
  fr_dbuff_t work_dbuff = FR_DBUFF(dbuff);
  ssize_t slen;
  uint8_t major, info;
  uint64_t value;

  /*
   *  get the next byte, which is a CBOR header.
   */
  slen = fr_dbuff_out(&major, &work_dbuff);
  if (slen <= 0) {
  no_data:
    fr_strerror_const("Invalid cbor - insufficient data");
    return FR_TYPE_NULL;
  }

  info = major & 0x1f;
  major >>= 5;

  switch (major) {
  case CBOR_INTEGER:
    return FR_TYPE_UINT64;

  case CBOR_NEGATIVE:
    return FR_TYPE_INT64;

  case CBOR_STRING:
    return FR_TYPE_STRING;

  case CBOR_OCTETS:
    return FR_TYPE_OCTETS;

  case CBOR_ARRAY:
    if (!pair) return FR_TYPE_GROUP;
    break;

  case CBOR_MAP:
    return FR_TYPE_TLV;

    /*
     *  Look at the tag to determine what it is
     */
  case CBOR_TAG:
    slen = cbor_decode_integer(&value, info, &work_dbuff);
    if (slen < 0) break;

    switch (value) {
    case 1:
    case 1001:
      return FR_TYPE_DATE;

    case 1002:
      return FR_TYPE_TIME_DELTA;

    case 48:
      return FR_TYPE_ETHERNET;

    case 52:
      slen = fr_dbuff_out(&major, &work_dbuff);
      if (slen <= 0) goto no_data;

      major >>= 5;

      if (major == CBOR_ARRAY) {
        return FR_TYPE_IPV4_PREFIX;
      }
      return FR_TYPE_IPV4_ADDR;

    case 54:
      slen = fr_dbuff_out(&major, &work_dbuff);
      if (slen <= 0) goto no_data;

      major >>= 5;

      if (major == CBOR_ARRAY) {
        return FR_TYPE_IPV6_PREFIX;
      }
      return FR_TYPE_IPV6_ADDR;

    default:
      break;
    }

    break;

  case CBOR_FLOAT:
    /*
     *  In-place values are special. false / true / NULL
     */
    if (info < 24) {
      if ((info == 20) || (info == 21)) return FR_TYPE_BOOL;

      return FR_TYPE_NULL;
    }

    return FR_TYPE_FLOAT64;
  }


  /*
   *  No idea.  :(
   *
   *  @todo - also check the cbor data, and return the length of cbor data which needs to be
   *  converted to data type 'octets'.  This work involves mostly parsing the cbor data, which isn't
   *  trivial.
   */
  fr_strerror_const("Invalid cbor - unable to determine data type");
  return FR_TYPE_NULL;
}

static ssize_t cbor_decode_pair(TALLOC_CTX *ctx, fr_pair_list_t *out, fr_dbuff_t *dbuff,
        fr_dict_attr_t const *parent, bool tainted, int depth)
{
  fr_dbuff_t work_dbuff = FR_DBUFF(dbuff);
  uint8_t header, major, info;
  bool indefinite;
  ssize_t slen;
  fr_pair_t *vp;
  uint64_t value = 0;
  fr_dict_attr_t const *da;

  FR_DBUFF_OUT_RETURN(&header, &work_dbuff);

  /*
   *  We require a 2-element array(attribute number, value)
   */
  if (header != (((CBOR_MAP) << 5) | 1)) {
    fr_strerror_printf("Invalid cbor header - expected map of 1 elements, got %02x", header);
    return -1;
  }

  /*
   *  This should be a CBOR_INTEGER.
   */
  FR_DBUFF_OUT_RETURN(&major, &work_dbuff);

  info = major & 0x1f;
  major >>= 5;

  if (major != CBOR_INTEGER) {
    fr_strerror_printf("Invalid cbor - expected 'integer', got major type %d",
           major);
    return -1;
  }

  slen = cbor_decode_integer(&value, info, &work_dbuff);
  if (slen < 0) {
    return_slen;
  }

  /*
   *  If the nesting is too deep, decode as raw octets.  We have to do this manually in CBOR,
   *  because the other protocols create a da_stack which limits the depth.
   */
  if (depth >= FR_DICT_MAX_TLV_STACK) goto raw;

  da = fr_dict_attr_child_by_num(parent, value);
  if (!da) {
    fr_type_t type;

    type = cbor_guess_type(&work_dbuff, true);
    if (type == FR_TYPE_NULL) return -fr_dbuff_used(&work_dbuff);

    if (depth >= FR_DICT_MAX_TLV_STACK) {
    raw:
      type = FR_TYPE_OCTETS;
    }

    /*
     *  @todo - the value here isn't a cbor octets type, but is instead cbor data.  Since cbor
     *  is typed, we _could_ perhaps instead discover the type from the cbor data, and then
     *  use that instead.  This would involve creating a function which maps cbor types to our
     *  data types.
     */
    da = fr_dict_attr_unknown_typed_afrom_num(ctx, parent, value, type);
    if (!da) return -fr_dbuff_used(&work_dbuff);
  }

  vp = fr_pair_afrom_da(ctx, da);
  if (!vp) {
    fr_strerror_const("Out of memory");
    return -fr_dbuff_used(&work_dbuff);
  }

  /*
   *  Leaf values are easy.
   */
  if (fr_type_is_leaf(da->type)) {
    slen = fr_cbor_decode_value_box(vp, &vp->data, &work_dbuff, da->type, da, tainted);
    if (slen < 0) {
      talloc_free(vp);
      return_slen;
    }

    goto done;
  }

  fr_assert(fr_type_is_structural(da->type));

  switch (da->type) {
    /*
     *  All of these are essentially the same.
     */
  case FR_TYPE_VENDOR:
  case FR_TYPE_VSA:
  case FR_TYPE_TLV:
    parent = vp->da;
    break;

    /*
     *  Groups reparent to the ref.
     */
  case FR_TYPE_GROUP:
    parent = fr_dict_attr_ref(vp->da);
    fr_assert(parent != NULL);
    break;

  default:
    fr_strerror_printf("Invalid data type %s for child %s of %s",
           fr_type_to_str(da->type), vp->da->name, parent->name);
    talloc_free(vp);
    return -1;
  }

  /*
   *  This should be a CBOR_ARRAY.
   */
  FR_DBUFF_OUT_RETURN(&major, &work_dbuff);

  info = major & 0x1f;
  major >>= 5;

  if (major != CBOR_ARRAY) {
    /*
     *  Allow NULL as a synonym for "no children".
     */
    if ((major == CBOR_FLOAT) && (info == 22)) goto done;

    talloc_free(vp);
    fr_strerror_printf("Invalid cbor - expected 'array', got major type %d",
           major);
    return -1;
  }

  if (info == 31) {
    value = ~0;
    indefinite = true;

  } else {
    slen = cbor_decode_integer(&value, info, &work_dbuff);
    if (slen < 0) {
      talloc_free(vp);
      return_slen;
    }

    indefinite = false;
  }

#ifdef STATIC_ANALYZER
  if (value > fr_dbuff_remaining(&work_dbuff)) return -1;
#endif

  /*
   *  Loop until we decode everything.  For simplicity, we handle indefinite and definite
   *  length arrays in the same loop.
   */
  for (/* nothing */; value > 0; value--) {
    /*
     *  Require at least one byte in the buffer.
     */
    if (fr_dbuff_extend_lowat(NULL, &work_dbuff, 1) == 0) {
      talloc_free(vp);
      return -fr_dbuff_used(&work_dbuff);
    }

    /*
     *  Peek ahead for a break.
     */
    header = *fr_dbuff_current(&work_dbuff);
    if (header == 0xff) {
      if (!indefinite) {
        talloc_free(vp);
        fr_strerror_const("Unexpected 'break' found in cbor data");
        return -fr_dbuff_used(&work_dbuff);
      }

      /*
       *  Done!
       */
      fr_dbuff_advance(&work_dbuff, 1);
      break;
    }

    slen = cbor_decode_pair(vp, &vp->vp_group, &work_dbuff, parent, tainted, depth + 1);
    if (slen <= 0) {
      talloc_free(vp);
      return_slen;
    }
  }

done:
  FR_PAIR_APPEND(out, vp);
  return fr_dbuff_set(dbuff, &work_dbuff);
}

ssize_t fr_cbor_decode_pair(TALLOC_CTX *ctx, fr_pair_list_t *out, fr_dbuff_t *dbuff,
          fr_dict_attr_t const *parent, bool tainted)
{
  return cbor_decode_pair(ctx, out, dbuff, parent, tainted, 0);
}

/*
 *  @todo - cbor_print
 *  [] for array
 *  [_...] for indefinite array
 *  {a:b} for map
 *  digits for integer
 *  'string' for string
 *  h'HHHH' for octets
 *
 *  https://datatracker.ietf.org/doc/html/draft-ietf-cbor-edn-literals
 */

Coverage Report

Created: 2026-09-28 06:27